From 9f55d2f14eb3953bbffaea1f5aeeb4ac2f1f0cb3 Mon Sep 17 00:00:00 2001
From: ChaosExAnima <ChaosExAnima@users.noreply.github.com>
Date: Fri, 20 Feb 2026 13:14:59 +0100
Subject: [PATCH] add generic typed matcher for ease of building off legacy
 actions

---
 app/javascript/mastodon/store/typed_functions.ts | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/app/javascript/mastodon/store/typed_functions.ts b/app/javascript/mastodon/store/typed_functions.ts
index 79bca08a52f..dec52771d98 100644
--- a/app/javascript/mastodon/store/typed_functions.ts
+++ b/app/javascript/mastodon/store/typed_functions.ts
@@ -1,6 +1,8 @@
 import type {
+  Action,
   ActionCreatorWithPreparedPayload,
   GetThunkAPI,
+  UnknownAction,
 } from '@reduxjs/toolkit';
 import {
   createAsyncThunk as rtkCreateAsyncThunk,
@@ -310,3 +312,15 @@ export function createDataLoadingThunk<
     },
   );
 }
+
+/**
+ * Provides a type guard for legacy string actions.
+ * @param type The action type string.
+ * @example
+ * if (matchAppAction('my_action_type')(action)) {
+ *    // action is now typed
+ * }
+ */
+export function matchAppAction<TAction extends Action>(type: TAction['type']) {
+  return (action: UnknownAction): action is TAction => action.type === type;
+}